Embodiments of the present invention relate to a magnetic mass for an electric machine rotor and also relates to such a rotor. Embodiments of the present invention also relate to a manufacturing process for such a rotor.
The document EP-A-0 609 645 describes a rotor comprising a magnetic mass and a short-circuit cage. The short-circuit cage comprises two short-circuit rings and a plurality of busbars each electrically connecting the short-circuit rings.
However, such a rotor has a relatively low power factor, of around 0.7 to 0.8. For a technical machine, the power factor is defined as the ratio between active power and apparent power. More the power factor is of major value, approaching the value 1, less excitation current is necessary for the rotor, a very high mechanical torque value for the rotor thus being available for the same electrical power at terminals of the electric machine.